Nowadays, portable containers (of the type of suitcases, trunks, trolley cases etc.) are widely used, and are constituted by two half-shells which are mutually articulated and are kept in the closed configuration by one or more locking elements (or locks), which are deactivateable on command in order to allow access to the internal compartment of the container.
Some of these containers, in order to meet specific requirements of some market segments and of various classes of professional users, must further be capable of ensuring a high resistance to shocks (without deformations of the structure and, still less, damage to what is being transported inside) and a total hermetic seal (thus preventing infiltrations into the compartment of water, air, dust and the like).
To this end, use is thus made of locking elements that, in the closed configuration of the container, are capable of mutually locking, and with force, two respective lips which protrude from the half-shells, and which are usually provided with perimetric gaskets.
In more detail, such elements comprise a clamp, which is articulated to one of the lips and is provided, at the opposite end, with a curved appendage that can engage elastically with the other lip, so as to achieve the desired mutual locking, when the two half-shells of the container are arranged in the closed configuration.
Such implementation solution is not however devoid of drawbacks.
Precisely because of the necessity to ensure the hermetic seal and excellent locking, even in the event of violent impacts, it is necessary to overdimension the clamp (and more generally the closure element) and/or to arrange a plurality of clamps along the protruding lips: this results first of all in an unwanted increase in the cost, structural complexity and, especially, the space occupation of the element, which on the contrary should be kept as small as possible (as will be made clearer in the following paragraphs).
Such necessities are evidently even more felt (and with them the drawbacks mentioned earlier) for bigger containers: in these in fact the surfaces of the half-shells, which are very extensive, are more subject to bending stresses, and can thus easily warp and be deformed during use, thus impairing the correct coupling at the lips (and thus compromising the seal).
In addition, it should be noted that often the manufacturers are forced to use levers, release buttons and other, similar contrivances, in order to enable the user to actuate the clamps with which the containers are provided, without requiring excessive effort.
This further increases the complexity, cost and space occupation of the closing elements described above, thus in fact exacerbating the drawbacks explained above.
It thus appears evident that trunks, suitcases and trolley cases of the type described above are provided externally with closing elements that are excessively cumbersome, and thus are such as to be above all inconvenient per se.
In addition, they are found to be entirely inadequate when the available space, as very often happens, is greatly limited by the mandatory presence of handles, padlocks, labels, openable doors, or by other construction-related requirements. Such elements in fact do not make it possible to find a convenient placement for the closing elements (and sometimes even for the protruding lips), still less leave available the space necessary for the rotation of their moving parts, during opening and closing.